**1. Introduction**

In diabetes (DM), chronic complications related to the direct or indirect effects of prolonged hyperglycemia on the vasculature have been classified into macrovascular and microvascular complications, depending on the size of affected vessels and the pathophysiological mechanisms involved. Microvascular disease includes retinopathy, nephropathy and neuropathy.

Diabetic retinopathy, one of the first manifestations of microvascular disease, remains today, despite improvements in monitoring and treatment, one of the leading causes of blindness worldwide. Epidemiological studies estimate that approximately 40% of subjects with DM type I over 40 years of age have retinal microvascular changes, of which 8.2% exhibit impaired visual acuity [1, 2]. Both DM types are associated with impaired retinal microcirculation. After 20 years

from the onset of DM, almost all patients with type 1 DM (T1DM) and over 60% of those with type 2 DM (T2DM) will be affected [3]. Furthermore, decreased vision as a result of diabetic retinopathy has a negative impact on the quality of life of patients and their ability to successfully manage DM [4].

Diabetic foot results from diabetic neuropathy and/or peripheral arterial disease and affects annually between 9.1 to 26.1 million [5]. It is a chronic disabling and progressive complication, with potential deformities, chronic ulcerations and infections. Diabetic foot ulcers (DFUs) are encountered in 15% of DM patients, of whom 15-20% reach amputations. The latter lead to increased morbidity and decreased quality of life, but also an important burden on national healthcare systems, with increased health costs and hospitalization [6, 7].
